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Spdx-Java-Library

Maven Central Java CI with Maven

Java library which implements the Java object model for SPDX and provides useful helper functions.

The API documentation is available at: https://spdx.github.io/Spdx-Java-Library/

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Library Version Compatibility

Library version 2.0.0 and higher is not compatible with previous versions of the library due to breaking changes introduced in SPDX 3.0.

The library does support the spec versions 2.X and 3.X.

See the README-V3-UPGRADE.md file for information on how to upgrade from earlier versions of the library.

Storage Interface

  • The Spdx-Java-Library allows for different implementations of SPDX object storage.
  • The storage facility implements the org.spdx.storage.IModelStore interface. This is a low level Service Provider Interface (SPI).
  • The ISerializableModelStore extends the IModelStore and supports serializing and de-serializing the store to an I/O Stream. This interface is currently used to implement JSON, XML, YAML, and RDF/XML formats.
  • The default storage interface is an in-memory Map which should be sufficient for light weight usage of the library.

Storage Interface Usage

  • Most common use of the library would de-serialize an existing SPDX document using one of the supported formats and model stores.
  • To create SPDX objects from scratch, simply create the Java objects found in the org.spdx.library.model package.
  • The model follows the SPDX Object Model.
  • The model objects themselves are stateless and do not store information.
  • All information is retrieved from the model store when properties are access.
  • Storage to the classes will store the updates through the use of the storage interface.

Multi-Threaded Considerations

The methods enterCriticalSection and leaveCriticalSection are available to support multi-threaded applications.

These methods serialize access to the model store for the specific SPDX document used for the SPDX model object.

Getting Started

The library is available in Maven Central as org.spdx:java-spdx-library (note the order of the word "java-spdx").

If you are using Maven, you can add the following dependency in your POM file:

<dependency>
  <groupId>org.spdx</groupId>
  <artifactId>java-spdx-library</artifactId>
  <version>(,2.0]</version>
</dependency>

The API documentation is available at: https://spdx.github.io/Spdx-Java-Library/

There are a couple of static classes that help common usage scenarios:

  • org.spdx.library.SpdxModelFactory supports the creation of specific model objects
  • org.spdx.library.model.license.LicenseInfoFactory supports the parsing of SPDX license expressions, creation, and comparison of SPDX licenses

Configuration options

Spdx-Java-Library can be configured using either Java system properties or a Java properties file located in the runtime CLASSPATH at /resources/spdx-java-library.properties.

The library has these configuration options:

  1. org.spdx.useJARLicenseInfoOnly - a boolean that controls whether the (potentially out of date) listed license information bundled inside the JAR is used (true), vs the library downloading the latest files from the SPDX website (false). Default is false (always download the latest files from the SPDX website).
  2. org.spdx.downloadCacheEnabled - a boolean that enables or disables the download cache. Defaults to false (the cache is disabled). The cache location is determined as per the XDG Base Directory Specification (i.e. ${XDG_CACHE_HOME}/Spdx-Java-Library or ${HOME}/.cache/Spdx-Java-Library).
  3. org.spdx.downloadCacheCheckIntervalSecs - a long that controls how often each cache entry is rechecked for staleness, in units of seconds. Defaults to 86,400 seconds (24 hours). Set to 0 (zero) to have each cache entry checked every time (note: this will result in a lot more network I/O and negatively impact performance, albeit there is still a substantial performance saving vs not using the cache at all).

Note that these configuration options can only be modified prior to first use of Spdx-Java-Library. Once the library is initialized, subsequent changes will have no effect.

Initialization

The first thing that needs to be done in your implementation is call SpdxModelFactory.init() - this will load all the supported versions.

If you are programmatically creating SPDX data, you will start by creating a model store. The simplest model store is an in-memory model store which can be created with store = new InMemSpdxStore().

A copy manager will be needed if you are working with more than one store (e.g. a serialized format of SPDX data and in memory). If you're not sure, you should just create one. This can be done with copyManager = new ModelCopyManager().

The first object you create will depend on the major version:

  • For SPDX 2.X, you would start by creating an SpdxDocument.
    • The factory method SpdxDocument document = SpdxModelFactory.createSpdxDocumentV2(IModelStore modelStore, String documentUri, IModelCopyManager copyManager) will create a new SPDX document.
    • Once created, you can use the setters to set the specific fields.
    • You can then use the convenience create methods on the document to create additional SPDX objects (e.g. document.createSpdxFile(...));
  • For SPDX 3.X, you will start with a CreationInfo class.
    • The factory method CreationInfo creationInfo = SpdxModelClassFactory.createCreationInfo(IModelStore modelStore, String createdByUri,String createdByName, @Nullable IModelCopyManager copyManager) will create and initialize a CreationInfo with today's date and the Agent information.
    • To create any additional objects, you can use the builder convenience methods from the creationInfo (or any Elements created by the creationInfo) e.g. creationInfo.createSoftwareSpdxFile(String spdxFileObjectUri).
    • The created objects will copy the creationInfo.

Update for new versions of the spec

To update Spdx-Java-Library, the following is a very brief checklist:

  1. Create a Java .jar file for the new version which contains an implementation of ISpdxModelInfo - typically named SpdxModelInfoVXXX - where "XXX" is the version of the spec.
  2. Update the SpdxModelFactory source file to load the model info by adding the line ModelRegistry.getModelRegistry().registerModel(new SpdxModelInfoVXXX()); in the static block at the very beginning of the class.
  3. If there are any conversions that are needed when copying to or from the new model version, add conversion code to the ModelCopyConverter class.
  4. Update SpdxModelFactory unit test for the highest version check

Development Status

Note: This library is currently unstable, and under development. Reviews, suggestions are welcome. Please enter an issue with any suggestions.